(This is mainly for SIGGRAPH, but can be adapted to other scenarios.)
Check out Aaron Hertzmann’s blog about rebuttal as well. In short, our goal of the rebuttal is to convince the reviewers to accept the paper, regardless of the official rules.
First of all, understand the rebuttal process by reading the relevant information, e.g. the email from paper chair as well as the SIGGRAPH website. These already provide useful hints. Below are my additional suggestions.
The basics
Rebuttal is a scripted process, and it is not about the scores. The content does depend on the reviews, but the process should remain the same if you are rational.
Rebuttal does make a difference, not always, but frequent enough to worth the efforts. I have had a paper accepted with average score $<$ 2.8, and a paper rejected with average score $>$ 4.0 (out of a 5.0 scale).
The psychology
It is human nature to rate their own works more highly than others would. So you will likely get disappointed, especially for venues with high quality bar like SIGGRAPH. Lowering your expectation can help. (I usually assume the worst case scenario.) As you become more experienced you might be able to stand in the reviewers shoes and judge your own work more objectively with less emotional attachment. But before that, I suggest following a pre-scripted procedure.
Procedure
Feel free to design your own procedure that works best for you, but here is mine for your reference. I designed it in a way so that in no stage would your emotion be easily slipped in.
. Save the review files somewhere (svn check-in the plain text .htm files if you are collaborating with me).
. Read the reviews once, grouped by reviewers instead of questions. This will give you a more coherent impression of each reviewer’s general stance. It also allows you a chance to vent (in a non-harmful way); if you feel angry now, go punch the wall or something. Do not proceed to the following stages until you are sufficiently relieved.
. Prepare a blank document for the rebuttal text. If you are collaborating with me via svn, check in the document first.
. Read the reviews again, and write down the questions in the rebuttal document that remotely seem to need answering. (Yes, we should keep the rebuttal document reasonably short and try not to answer every single question, but we need to identify the important ones first. This is why I prefer to be more conservative in listing questions in this early stage.) Focus on the questions now and do not worry about answers in this stage.
. It is likely that different reviewers might ask the same or similar questions. If so, consolidate the questions and mark the corresponding reviewer ids.
. Sort the questions in a roughly prioritized order, put in front these questions that are more important (e.g. factual misunderstanding/misinterpretation or specific questions asked by reviewers that they wish you to address in the rebuttal). Do not remove any question at this stage.
. Start adding answers to the questions. In the process, we might need to reorganize the questions and their orders. This is a natural process of writing rebuttal, just like writing the paper. We will iterate multiple rounds until every co-author is satisfied with the document.
. The official suggestion is to keep the rebuttal document short, but I would prefer to make it longer than necessary instead of risking omit important questions. (It is not always easy to correctly identify which questions are really important.) Of course the rebuttal text cannot run over the size limit (e.g. 2000 words), but to avoid confusing the reviewers, I usually separate the rebuttal into two parts: the main part for major and common questions, and the detailed part for individual reviewers. My personal experience as a reviewer (both primary/secondary and tertiary) is that I would not mind seeing a rebuttal running up to the length as long as the main part is clearly marked and shown up front. This allows me the flexibility to skip the more detailed parts if necessary. I have also observed that the reviewers tend to feel respected if the authors answer their questions, even for relatively minor ones.
. Before sending out the rebuttal text, add a short paragraph in the very beginning to thank all the reviewers for their effort in reading your paper and all the wonderful comments they have made.
. Submit the rebuttal. Do it early instead of waiting for the last minute, for obvious reasons. If the mechanism allows you to overwrite the previous uploads, definitely do so early. You can update the document later.